The startechcom 12cm x 12cm x 25cm 4 34 x 4 34 x 1 pc case fan is an add in cooling fan designed to fit most computers it can be used to circulate cool air into the case or exhaust warm air out preventing problems due to overheating components a quiet running brushless ball bearing dc motor coupled with a high efficiency blade design is capable of moving 48 cfm cubic feet per minute of air power is supplied to the fan using a standard lp4 hard drive power connector pass through